K-Family
DC-DC Converters >100 W
Rugged Environment
150 W DC-DC (AC-DC) Converters
Input to output isolation
Single output: AK...LK 1000
Double output: AK...LK 2000
•
Extremely wide input voltage range
•
Input over- and undervoltage lock-out
•
Efficient input filter and built-in surge and transient
suppression circuitry
•
4 kV
rms
input to output isolation test voltage
•
Fully isolated outputs
•
Outputs open- and short-circuit proof
•
No derating over entire operating temperature range
Safety according to IEC 950
V
DE
C
K-Family
Table of Contents
Page
8.1
Description .................................................................. 8 - 2
Type Survey ................................................................ 8 - 3
Safety and Installation Instructions ............................. 8 - 4
Functional Description ................................................. 8 - 6
Electrical Input Data .................................................... 8 - 7
Electromagnetic Compatibility EMC ............................ 8 - 9
Electrical Output Data ............................................... 8 - 11
Supplementary Data ................................................. 8 - 19
Description of Options ............................................... 8 - 19
Immunity to Environmental Conditions ...................... 8 - 26
Mechanical Data ....................................................... 8 - 27
Type Key and Product Marking ................................. 8 - 28
Description
The K-family of DC-DC (AC-DC) converters represents a
broad and flexible range of power supplies for use in ad-
vanced electronic systems. Features include high effi-
ciency, high reliability, low output voltage noise and excel-
lent dynamic response to load/line changes.
The converter inputs are protected against surges and tran-
sients occuring on the source lines. Input over- and
undervoltage lock-out circuitry disables the outputs if the
input voltage is outside the specified ranges. Certain types
include an inrush current limitation preventing circuit break-
ers and fuses from being damaged at switch-on.
All outputs are open- and short-circuit proof and are pro-
tected against overvoltages by means of a built-in suppres-
sor diode. The outputs can be inhibited by a logic signal ap-
plied to the connector pin i. If the inhibit function is not used
pin 18 must be connected with pin 14 to enable the outputs.
LED indicators display the status of the converter and allow
visual monitoring of the system at any time.
Full input to output, input to case, output to case and output
to output isolation is provided. The modules are designed
and built according to the international safety standards
IEC 950 and have been approved by the safety agencies
VDE (Germany) and UL (USA). The UL Mark for Canada
has been officially recognized be regulatory authorities in
provinces across Canada.
The case design allows operation at nominal load up to
71°C in a free air ambient temperature. If forced cooling is
provided, the ambient temperature may exceed 71
°C
but
the case temperature must remain below 95
°C
under all
conditions.
A temperature sensor generates an inhibit signal which
disables the outputs if the case temperature
T
C
exceeds the
limit. The outputs are automatically re-enabled when the
temperature drops below the limit.
Various options are available to adapt the converters to in-
dividual applications.
The modules may either be plugged into 19 inch rack sys-
tems according to DIN 41494, or be chassis mounted.
Case: Aluminium, black finish, self cooling.
8-2
MELCHER
The Power Partners.
Edition 2/96 - © Melcher AG
Rugged Environment
Type Survey
DC-DC Converters >100 W
K-Family
Survey of Options see "Description of Options"
Different output voltages and currents may be set in accordance with customer specifications.
Table 1a: Type survey AK
Output 1
Output 2
Input Voltage Range
and Efficiency
1
Options
U
o nom
[V DC]
5.1
12.0
15.0
24.0
24.0
4
30.0
4
48.0
4
12.0
15.0
24.0
I
o nom
[A]
2
20.0
10.0
8.0
5.0
5.0
4.0
2.5
5.0
4.0
2.5
U
o nom
[V DC]
I
o nom
[A]
2
U
i min
...U
i max
8...35 V DC
AK 1001-7R
AK 1301-7R
AK 1501-7R
AK 1601-7R
AK 2320-7R
AK 2540-7R
AK 2660-7R
η
min
[%]
78
80
80
82
78
79
79
78
79
79
-9
D
V
6
P
T
B1
12.0
5
15.0
5
24.0
5
5.0
4.0
2.5
AK 2320-7R
AK 2540-7R
AK 2660-7R
Table 1b: Type survey BK, CK
Output 1
Output 2
Input Voltage Range and Efficiency
1
Options
U
o nom
[V DC]
5.1
12.0
15.0
24.0
24.0
4
30.0
4
48.0
4
12.0
15.0
24.0
I
o nom
[A]
2
25.0
12.0
10.0
6.0
6.0
5.0
3.0
6.0
5.0
3.0
U
o nom
[V DC]
I
o nom
[A]
2
U
i min
...U
i max
14...70 V DC
BK 1001-7R
BK 1301-7R
BK 1501-7R
BK 1601-7R
BK 2320-7R
BK 2540-7R
BK 2660-7R
η
min
[%]
79
81
83
84
80
80
80
80
80
80
U
i min
...
U
i max
28...140 V DC
CK 1001-7R
CK 1301-7R
CK 1501-7R
CK 1601-7R
CK 2320-7R
CK 2540-7R
CK 2660-7R
CK 2320-7R
CK 2540-7R
CK 2660-7R
η
min
[%]
79
82
82
86
80
82
84
80
82
84
-9
E
3
D
V
6
P
T
B1
Table 1c: Type survey DK, FK, LK
Output 1
Output 2
Input Voltage Range and Efficiency
1
Options
U
o nom
[V DC]
5.1
12.0
15.0
24.0
24.0
4
30.0
4
48.0
4
12.0
15.0
24.0
1
2
3
4
5
6
I
o nom
[A]
2
25.0
12.0
10.0
6.0
6.0
5.0
3.0
6.0
5.0
3.0
U
o nom
[V DC]
I
o nom
[A]
2
U
i min
…U
i max
44...220 V DC
DK 1001-7R
DK 1301-7R
DK 1501-7R
DK 1601-7R
DK 2320-7R
DK 2540-7R
DK 2660-7R
η
min
[%]
79
83
86
86
81
83
85
81
83
84
U
i min
...
U
i max
20...100 V DC
FK 1001-7R
FK 1301-7R
FK 1501-7R
FK 1601-7R
FK 2320-7R
FK 2540-7R
FK 2660-7R
FK 2320-7R
FK 2540-7R
FK 2660-7R
η
min
[%]
80
82
85
86
81
83
84
81
83
84
U
i min
...U
i max
88...372 V DC
(85…264 V AC)
LK 1001-7R
LK 1301-7R
LK 1501-7R
LK 1601-7R
LK 2320-7R
LK 2540-7R
LK 2660-7R
LK 2320-7R
LK 2540-7R
LK 2660-7R
η
min
[%]
79
84
84
85
81
83
84
81
83
84
-9
E
3
D
V
6
P
T
B1
12.0
5
15.0
5
24.0
5
6.0
5.0
3.0
DK 2320-7R
DK 2540-7R
DK 2660-7R
Efficiency at
U
i nom
and
I
o nom
.
If the output voltages are increased above
U
o nom
via R-input control, option P setting, remote sensing or option T, the output currents
should be reduced accordingly so that
P
o nom
is not exceeded.
Option E for C/D/E/LK types.
Series connection of output 1 and 2.
Second output semi-regulated.
Option V for A...LK 1001 types only.
Note:
EK types with an input voltage range of 67...385 V DC are available upon request.
Edition 2/96 - © Melcher AG
MELCHER
The Power Partners.
8-3
8.1
12.0
5
15.0
5
24.0
5
6.0
5.0
3.0
BK 2320-7R
BK 2540-7R
BK 2660-7R
K-Family
DC-DC Converters >100 W
Rugged Environment
Safety and Installation Instructions
Safety:
For safety reasons, the power supplies should be wired
via the female connector H15 or H15 S4 (according to
DIN 41612, see "Accessories") in order to meet national
and international safety requirements.
If the output circuit of a DC-DC converter is operator-acces-
sible according to the IEC 950 related safety standards, it
shall be an SELV circuit (Safety Extra Low Voltage circuit,
i.e. a circuit, separated from mains by at least basic insula-
tion, that is so designed and protected that under normal
and single fault conditions, the voltage between any two
conductors and between any conductor and earth does not
exceed 60 V DC).
In the following section an interpretation is provided of the
IEC 950 safety standard with respect to the safety status of
the output circuit. However, it is the sole responsibility of
the installer or user to assure the compliance with the rel-
evant and applicable safety standards.
If table below is observed, the output of a DC-DC converter
is considered to be an SELV circuit up to a nominal output
voltage of 36 V.
The converters correspond to safety class I equipment and
comply with IEC 950, EN 60950, VDE 0805 Part 100 (in-
cluding manufacturing surveillance), UL 1950, CSA C22.2
No. 950-95 and are VDE approved.
The connector has a leading earth connection pin which
ensures earth connection prior to any other.
The UL 1950 recognition limits the ambient operational
temperature range of the standard modules (-7) to
–25...50°C. In applications where the full operational tem-
perature range of –25...71
°C
under UL condition is re-
quired, forced cooling should be provided. The European
approval boards have in contrast accepted the converters
to be operated up to
T
A max
without any further precautions.
Installation Instructions
Installation must strictly follow the national safety regula-
tions. Pin 24 has to be connected to earth. A second fuse
should be installed in the wiring to pins 26/28 if:
– Local requirements demand an individual fuse in each
source line
– Input to protective earth impedance is high or undefined
– Phase and neutral of the mains are not defined (AC-DC
converters).
In applications where the inhibit function is not used, the
inhibit pin should be connected to the S– pin (K 1000) or
the Vo1– pin (K 2000) to enable the outputs.
Table 2: Insulation concept
Converter Nominal Minimum required grade of
type
mains
isolation, to be provided by
supply
the AC-DC front end,
voltage including mains supplied
(AC)
battery charger
Maximum Minimum required safety
output
status of the front end
voltage
output circuit
from the
front end
≤100
V
Primary circuit
Minimum required grade
of isolation between the
input and the output
provided by the
the DC-DC converter
Double or reinforced,
based on
AC 150 V and DC 100 V
Double or reinforced,
based on
AC 250 V and DC 100 V
Reinforced, based on
AC 250 V and DC 400 V
Resulting
safety
status
of the
DC-DC
output
SELV
circuit
8.1
AK, BK
≤150V
Operational
≤250V
Basic
≤100
V
Hazardous voltage
secondary circuit
(earthed or unearthed)
Primary circuit
CK, DK,
EK, FK,
LK
≤250V
Operational
≤400
V
Important Advice
Electric strength tests should not be repeated in the field. Improper test methods, for example overshooting or oscillating
test voltages, voltage slopes exceeding 1 kV/µs, internal Y-capacitors not carefully discharged, etc. can cause severe
damage to switching devices and ICs. Melcher AG will not honour any guarantee/warranty claims resulting from high
voltage field tests.
8-4
MELCHER
The Power Partners.
Edition 2/96 - © Melcher AG
Rugged Environment
DC-DC Converters >100 W
K-Family
Table 3: H15 and H15 S4 connector pin allocation
Pin
No.
4
6
8
10
12
14
16
18
20
Connector type H15 S4
AK 1000 (all), BK...LK 1001
Vo1+
Output 1
AK 2000
Vo2+
Output 2
Connector type H 15
BK…LK 1301/1501/1601
Vo1+
Vo1+
Vo1–
Vo1–
S+
S–
R
1
i
D
Output 1
BK…LK 2000
Vo2+
Vo2+
Vo2–
Vo2–
Vo1+
Vo1–
R
1
i
D
Output 2
Vo1–
S+
S–
R
1
i
D
3
V
3
Output 1
Sense
Sense
Control of
U
o1
Inhibit
Save data
ACFAIL
Current sharing
Protective earth
Vo2–
Vo1+
Vo1–
R
1
i
D
Output 2
Output 1
Output 1
Control of
U
o1
Inhibit
Safe data
Output 1
Sense
Sense
Control of
U
o1
Inhibit
Save data
Output 2
Output 1
Output 1
Control of
U
o1
Inhibit
Save data
22
24
2
26
28
30
32
1
T
T
Current sharing
Protective earth
T
Current sharing
Protective earth
T
Current sharing
Protective earth
Vi+ or N
Input or Neutral
Vi+
Input or Neutral
Vi+ or N
Vi+ or N
Vi– or P
Vi– or P
3
Input or Neutral
Vi+ or N
Vi+ or N
Vi– or P
Vi– or P
Input or Neutral
Vi– or P
Input or Phase
Vi–
2
Input or Phase
Input or Phase
Input or Phase
Feature R excludes option P and vice versa;
Leading pin (pregrounding);
Option D excludes option V and vice versa.
30/32
4/6
Type H15 S4
32
Type H15
4
Degree of Protection
Condition: Female connector fitted to the unit.
IP 30: All units except those with options P, D or V with
potentiometer adjustment.
IP 20: All units fitted with options which include poten-
tiometer setting.
Edition 2/96 - © Melcher AG
MELCHER
The Power Partners.
8-5
8.1
Fig. 1
View of module's male connectors
K-Family
Functional Description
DC-DC Converters >100 W
Rugged Environment
The input voltage is fed via an input fuse, an input filter, a
rectifier (LK types) and an inrush current limiter to the input
capacitor. This capacitor sources a single transistor forward
converter. Each output is powered by a separate secondary
winding of the main transformer. The resultant voltages are
rectified and their ripples smoothed by a power choke and
output filter. The control logic senses the main output volt-
age
U
o1
and generates, with respect to the maximum ad-
missible output currents, the control signal for the primary
switching transistor.
The second output of double output units is controlled by
the main output but has independent current limiting. If the
main output is taken into current limitation, the second out-
put voltage will fall as well and vice versa.
P
26
Y
16
18
3
28
2
1
20
Control circuit
22
12
4
6
Forward converter
(approx. 120 kHz)
Y
Input filter
Output
filter
8
10
5
4
Y
30
32
24
Y
14
Fig. 2
Block diagram of single output converters AK…LK 1000
P
–
+
16
8.1
26
28
Y
2
1
3
18
20
Control circuit
22
Forward converter
(approx. 110 kHz)
Y
Input filter
Output 1
filter
12
14
4
6
5
4
Y
Y
30
32
24
Output 2
filter
8
10
Y
Y
1
2
3
Transient suppressor (VDR) in C/D/E/F/LK types
Transient suppressor (diode) in A/B/C/FK types
Bridge rectifier in LK types
4
5
10
– +
Inrush current limiter in C/D/E/LK types (NTC or Opt. E),
-9 versions exclude the NTC
Input fuse
Fig. 3
Block diagram of symmetrical double output converters AK...LK 2000
8-6
MELCHER
The Power Partners.
Edition 2/96 - © Melcher AG
